Three Americans are hoping to make history together this weekend in Europe.
Devin, Dustin and Danielle Wahl could be the first trio of siblings to swim across the English Channel at the same time, CBS This Morning host Norah O'Donnell reports.
They're taking on the challenge in part to raise awareness about Alzheimer's, a disease that's affected their loved ones, and while they face extreme conditions, they are counting on family bonds to overcome rough ocean currents.
"It's just the Mount Everest of swimming," Devin said. "So there's a whole lot of factors that can go in to you being successful or not being successful."
Devin Wahl says training to swim the English Channel with his siblings has been grueling, and consists of more than just swimming about 10,000 yards a day, five days a week.
It's weight lifting three days a week, focusing on shoulders, arms, back and abs.
And even ice baths to get the body used to the long swim in the cold channel water.
The waterway averages 60 degrees, and it could take anywhere from 10 to 20 hours to complete the crossing.
While Devin is trying to build muscle, he's also working on putting on some fat, he said, "because that little extra layer of fat helps with insulating your body."
But he says preparing the mind tops the list.
"The most important thing is your mental capacity," he said. "You've got to continue pushing even when you want to give up and you probably will want to give up."
Devin is no stranger to endurance sports. He competed in Ironman Triathlons with his father, although that swim is much shorter, at around 2.5 miles.
Swimming the English Channel is a much more difficult feat. The channel is 21 miles wide at its most narrow point, but it's not a straight shot across. Strong currents can push swimmers from side to side for miles, making the swim much longer.
High tides can also create towering swells - not to mention the English channel is one of the busiest shipping lanes in the world.
While Devin has been preparing with a trainer in Baltimore, more than 1,500 miles away in Colorado, his siblings, 19-year-old Dustin and 21-year-old Danielle are training together.
Danielle, an accomplished college swimmer, is familiar with the challenge. She successfully conquered the channel last summer and did very well.
Danielle holds the record for the fastest English Channel swimming time for any American, man or woman, completing it in 9 hours 49 minutes.
"I've talked with them a lot about training and what they need to do to train, and just kind of what you go through mentally and physically out there," Danielle said.
Dustin is also a seasoned athlete, but this is his first time tackling a body of water as large as the Channel.
"You get a wrong current, or bad weather, or lightning, and those are all factors that you can't really control," Dustin said. "But when it comes to the distance and the cold water, I think I'm mentally strong enough and physically strong enough to complete it."
Danielle also warned her brothers about another well-known Channel challenge: jellyfish.
"That was a huge setback for me last year," Danielle said. "This time I just know what to expect and I feel like swimming through the jellyfish pods this time will be easier."
While Danielle already owns a spot in the Channel record books, she's looking forward to the chance to make history again, this time with her two brothers.